1. Field of the Invention
This invention relates generally to switches and, more particularly, to a switch that is adapted for use with a compartment having an access opening closable by a closure member and that is activated in response to the opening and closing of the compartment by the closure member. The switch is particularly adapted for use with storage compartments of the type found in automotive vehicles to control the energization of a lamp bulb used to illuminate the compartment.
2. Description of the Prior Art
Closure activated switches are presently used in a variety of fields including, for example, automotive vehicles, domestic appliances and alarm and anti-theft systems. In a typical prior construction, the switch includes a pushbutton or plunger that is biased by a spring into a protruding position and that is disposed so as to be depressed against the action of the spring upon the closing of the closure member. The plunger operatively engages other components within the switch so that, when the plunger is depressed, an electrical circuit through the switch is either made or broken. Examples of prior closure activated switches are shown in the following U.S. Pat. Nos. 2,615,083; 3,048,674; 3,157,756; 3,193,673; 3,393,281; 3,432,634; 3,440,373; and 3,609,265.
For most applications, and particularly for automotive applications, it is important that the closure activated switches be relatively economical to manufacture and install and, at the same time, durable in use. As can be appreciated from a review of the above patents, a major drawback of many prior switches is their relative complexity and relatively large number of operating parts. This complexity not only adds to the cost of manufacturing the switches, but also oftentimes increases the likelihood of their premature failure because of the number of parts that are susceptible to failure.
Another, more specific problem is often encountered with prior switches, particularly those of the type including a plunger that is depressed by a closure member. Generally, in such switches, the plunger must be depressed to a predetermined point before the switch is activated. Because of the nature of manufacturing conditions, particularly those in the automotive industry, the clearances between a closed closure member and a frame member associated therewith in which the switch is typically mounted are difficult to control. These clearances also in many cases vary during the life of a vehicle as a result of the numerous openings and closings of the closure member. If these clearances are, or become, too large, the switch is not activated when the closure member closes and the usefulness of the switch is defeated.